Mandrel and polisher for polishing and grinding devices



Nov. 28, 1939.

H. R. BERGER MANDREL AND POLISHER FOR POLISHING AND GRINDING DEVICES Filed Feb. 16, 1938 2 Shoots-Sheet 1 Herbert R. bf??- BY Nov. 28, 1939. H. RQBERGER I $181,474

MANDREL AND Pomsrmn FOR POLISHING AND GRINDING nsvxcas Filed Feb. 16, 1958 2 sums-sheet 2 HeI berIR. BY

Patented Nov. 28, 1939 UNITED STATES Q MANDREL AND POLISHER FOR POLISHING AND GRINDING DEVICES Herbert It. Berger,

J. F. Jelenko & 00.,

Application February 16, 1938, Serial No.

6 Claims.

The present invention relates to improvements in mandrels and polishers for use in grinding and polishing operations and having particular utility in dental and jewelry polishing and grinding.

An important object of the invention is the provision of a mandrel and polishers which are reversible in action and which can be operated in close spaces and around corners.

Another object of the invention is to provide a" mandrel and polishing head which can be connected and disconnected without removing the mandrel from the handpiece and in a very short time.

A'further object of the invention is the prowhich may be used with easily and rapidly changed for different types of operations.

A still further object of the invention isthe being shown in section,

ing end of the mandrel,

Figure 3 is a top plan view thereof, Figure 4 is a sectional View of the polishing head shown in Figure 1, parts being shown in elevation, v Figure 5 is a bottom plan view thereof, Figure 6 is a cross sectional view on the line 6-6 of Figure l,

polishing head,

Figure 8 is a similar view of a split cylinder type polishing head, i t Figure 9 is a side elevation of a grinding disk, Figure 1-0 is a similar view of another type of grinding disk,

Figure 11 is a sectional view of a dished-cone polishing head mounted on the end of a mandr parts of he mand el being hown i .6 6- 55: vation,

vision of a plurality of shapes and types of heads a single mandrel and polishing or grinding head.

1 is an elevation of a mandrel and polishing head embodying the invention, parts;

Figure 2 is a side elevation of the head-engag-,

Figure '7 is a perspective view of a cone-shaped Brooklyn, N. Y., assignor to New York, N. Y.

Inc.,

. Figure12 is a similar view of a large reinforced cone polishing head,

Figure 13 is an elevation of a of mandrel, v

Figure 14 is a similar view of the mandrel 5 with polishing head attached, parts of the head and mandrel being shown in section,

Figure 15 is an elevation thereof with the clamping sleeve broken away,

Figure 16 is a sectional of Figure 14.

Figure 1'7 is an elevation of the mandrel with the sleeve in clamping position,

Figure 18 is a side elevation of a split cylinder grinding head for use with this type of mandrel, 15 theflared position of the head being shown in dotted lines,

Figure 19 is an elevation of a polishing cup,

Figure 20 is anelevation of a grinding disk,

modified form Figure 21 is a sectional view of another form 20 of grinding disk, parts being shown in elevation,

Figure 22 is a similar view of still another form of grinding disk,

Figure 23 is an head tang. and, 25

. Figure 24 is a view at right angles to Figure 23.

. In the drawings, wherein for the purpose of illustration is shown a preferred embodiment of the invention, the numeral 25 designates the body or shaft of amandrel'adapted to be re- 30 ceived in a rotatable chuck for grinding or polishing. The head of the mandrel is enlarged and comprises a tapered or conical point 26 and a cylindrical skirt 21 spaced concentrically from the point 26 and terminating at a point spaced a substantial distance from the tip of the point; 26. The skirt 2! is connected at its lower end to the mandrel body or shaft by a bottom wall which merges into the shaft 25. The skirt 21 maybe formed integrally with the mandrel or 40 it may be separately formed and connected thereto by molding or the like.

The skirt 2'! is provided with three evenly spaced reentrant notches or cutaway portions 28 which are enlarged at their lower ends, as seen 45 in Figure 3, and which form three spaced arcuate arms or prongs 29 with curved upper edges. The prongs 29 are widest adjacent their upper ends, and are of a length not greater than half the length of point 26.

The polishing and grinding heads may be of numerous shapes and of varying materials. For polishing, a rubber head in which some suitable abrasive is incorporated, may be employed. The. abrasive may be pumice, emery,

elevation of a modified form of view on line [6-46 10 I oxide of tin, 55,

rouge, or the like, and mixtures of these abrasives may be used. In place of rubber felt, or other suitable material, may be used and have the desired abrasive incorporated therein. The grinding wheels may be charged with carborundum or may be stone wheels or carborundum wheels. The polishing heads may take various forms, such as disks, cups, cones, points or split cylinders, but whatever the shape of the polisher or grinder, a connecting tang is provided to be engaged by the mandrel point and prongs. In place of a head in which abrasive material is incorporated, a plain head may be used with an abrasive paste.

In Figures 1, 4, 5 and 6 a polishing disk 30 is of rubber having' an abrasive incorporated therein, and having a centrally disposed, cylindrical tang 3! depending therefrom. The tang 3! has an extension 32 of reduced diameter.

through which a tapered bore 33 extends centrally to a point adjacent the upper surface of the disk, as illustrated in Figures 1 and 4. The bore 33 is adapted to removably receive the mandrel point 23 as indicated in Figure 1.

Three tabs 34 form extensions of tang 3 i, being evenly spaced about reduced extension 32 and connected thereto. Between the tabs 34, arcu ate slots or spaces 35 separate the reduced extension 32 from the body of tang 3i and are adapted to receive the prongs 29 of the mandrel.

The tang 3|, extension 32 and tabs 34, being of rubber, are flexible and resilient. The tabs 34 are of a shape which substantially corresponds with the shape of notches 28 and are adapted to be received in said notches. When it is desired to connect the mandrel with the head 30, point 26 is inserted in bore 33, tabs 34 are aligned with notches 28 and the head forced onto the mandrel until the prongs 29 are received in spaces 35 and point 26 is embedded in bore 33, as indicated in Figure 1. When forced into this position, tabs 34 fit into notches 28, being sufliciently deformable to enter the narrow upper ends of the notches. When the head is in the position shown in Figure 1, it will rotate with the mandrel in either direction, without being disconnected from the mandrel. The point 26 stiffens and supports the head 33 and expands and forces the parts of the rubber tang into intimate engagement with the prongs 23 and skirt 2?. Although firmly supported centrally by means of point 26 and prongs 29, the head 30 is allowed to flex at points spaced from its axis.

In Figure 7 the head is shown as in the form of a cone 36 or point having the tang 3i and. tabs 34 as in Figures 1 to 6. In Figure 8 a split cup or cylinder 37 is similarly provided with a tang to engage the mandrel. In operation, the split portions of the cylinder 31 will spread out for polishing, producing a brush action.

In Figure 9, a grinding disk 38 either charged with co-rborundum or formed from carborundum or the like, is provided with a rubber or other flexible tang 39 attached centrally thereof and adapted to engage the mandrel. In Figure 10,

a grinding stone 4i? is similarly provided with a,

flexible tang 39 secured centrally of the stone 41]. With the construction shown in Figures 9 and 10, a rigid or substantially rigid stone or wheel may be made flexible by the use of a flexible core and tang for engaging the mandrel.

In Figure 11 the cone head is dished inwardly to form an extended point 4| into which the mandrel point 2% extends to strengthen the head. In the larger cones, such as illustrated at 42 Figure 12, the bore of the head may be provided with a metal sleeve 43 to receive the mandrel point 26. The sleeve 43 is incorporated in the head and serves to increase the effective length of the mandrel point 26 and further strengthen the head 42.

It will be seen that the heads may be rotated in either direction without becoming disengaged from the mandrel. In the polishing of teeth, this reversibility of action is necessary to permit all\ sides of filling to be polished without danger of rubbing the filling away from the margins of the tooth. In ascrew type mandrel, the head can only be rotated in one direction and cannot be used for polishing where a reverse rotation is required. The heads may be easily and quickly changed, and the various types of head permit polishing and grinding in otherwise inaccessible places. The use of heads having abrasives incorporat'ed therein permit polishing without the use of pastes While the split cylinder type of head gives the desired brush action in cleaning and polishing. The heads having oxide of tin or rouge incorporated therein will produce a high shine or luster without the use of a paste or a cleaning compound.

Where a rubber or flexible tang is used with a stone or similar head, as in Figures 9 and 10, the desired flexibility is obtained, and when the tang wears out or breaks, it can be replaced without replacing the entire head.

In Figures 13 to 24, a modification of the invention is shown. The mandrel 44 is provided with an elongated tapered point or pin 46 surrounded by a plurality of spring arms 41 secured to the mandrel at the base of the point 46. The spring arms 41 are spaced from the point 46 and are separated by longitudinal slots 43. The arms 41 form a split cylinder adjacent their ends, and then converge to the mandrel at the base of the point'46. A tapered sleeve 43 surrounds the arms 41 and is'fr-eely slidable on the mandrel. The

upper end of sleeve 43 is knurled or serrated to aiford a grip for operating the sleeve.

The polishing head 50 may be of rubber or other suitable material in which an abrasive may be incorporated, and is provided with a depending cylindrical tang 5|. A central bore 52 extends through the tang and into the head 50 and is adapted to receive the point 46 of the mandrel which extends a substantial distance beyond the ends of the arms 41. The spring arms i! normally spring outwardly away from the mandrel point 43 so that the tang 5| may be inserted between them. When it is desired to attach the head to the mandrel, the point 46 is forced into the bore 52 in the head and the tang 5i forced down between the ends of the spring arms 47. The inner surfaces of the spring arms 41 are preferably serrated or knurled adjacent their upper ends to grip the tang 51. When the tapered sleeve 49 is moved up over the spring arms 41 to the position shown in Figures 14 and 15, the spring arms are forced into engagement with the tang 5i, firmly gripping. it and holding it against movement relative to the mandrel. The tapered pin 46 tends to spread the tang 5i against the spring arms. The head may be quickly released by moving the sleeve 49 into the position shown in Figure 13 and withdrawing the head from the pin 4%.

In Figure 18 a split cylinder 53 similar to that shown in Figure 8 is illustrated with a tang 54 to engage the mandrel of Figures 13, 14 and 15. In Figure 19 a cup 55 is shown with a similar tang 54'. The disk 56 of Figure 20 may be ofrubextend into the slots skirt-like member, and said tang having slots ber having pumice or other abrasive incorporated therein, and has a tang ii! for engagement with the mandrel 44.

In the stone or carborundum wheel of Figure 21 a central core 580i rubber or other flexible material formed in the wheel and has a depending tang 59 for engagement with the mandrel. Because of the flexible tang and core, the wheel will have the desired flexibility. In Figure 22 the disk 3% is of rubber in which carborundum is incorporated. A rubber flanged core (ii is centrally secured in the disk iii! and has a depending tang G2 to engage the mandrel M.

In place of the plain tangs shown in Figures 14 to 22, the tangs may be provided with longitudinal flanges or ribs 63 as indicated in Figures 23 and 24. When heads having the flanges 63 are mounted on the mandrel M, the flanges (33 will extend into the slots 48 between adjacent spring arms 4i and be, gripped by the arms when the sleeve is is forced into clamping position. The flanges 63 will render impossibleany rotation of the head relative to the mandrel.

The mandrels 25 and 44 may be connected to any suitable chuck, such as a straight or right angle hand piece for dental use, and the mandrel may have a plain lower end as in Figures 13 and 14 or a grooved and notched end for certain types of chucks, as indicated at 64 in Figure 1'7.

Either form of mandrel and polishing head and tang may be employed for a firm connection permitting easy and rapid changing of the heads and allowing rotation of the heads in either direction. The various forms of heads permit all types of polishing and grinding for various types of work. On the form of head shown in Figures 13 to 24, the tangis provided with a slight downward flare so that it is larger at its lower end than at its juncture with the head. This construction permits the knurled or serrated ends of the spring arms to obtain a firm grip.

While I have drawn and described the preferred embodiment of the invention, it is to be understood that various changes in the size, shape and arrangement of parts may be resorted to without departing from the spirit of the invention or the scope of the subjoined claims.

Having thus described my invention what I' claim and desire to protect by Letters Patent is:

I.- In a device of the character described, a mandrel having a skirt-like member slotted to form a plurality of prongs, a pin arranged within the skirt-like member and forming a continuation of the mandrel, said pin being spaced concentrically from the prongs and extending a substantial distance therebeyond', a head having a resilient tang adapted to be received within the skirtlike member, there being a bore extending through the tang and into the head to said tang having a plurality of tabs adapted to between the prongs of the between the tabs to receive the prongs of the skirt-like member.

2. In a device of the character described, a

receive the pin,

mandrel form a plurality of prongs, said prongs being widest adjacent their upper ends, a tapered pin arranged within the skirt-like member and forming a continuation of the mandrel, said tapered pin being spaced concentrically from the prongs and extending a substantial distance therebeyond, and a head having a resilient tang adapted to be received between the prongs, there being a tapered bore extending through the tang and into the head to receive the tapered pin, said tanghaving a plurality of tabs widest at their lower ends and adapted to extend into the slots between the prongs of the skirt-like member, and said tang having slots between the tabs to receive the prongs.

3. In a device of the character described, a mandrel having a skirt-like member adjacent one end, a pin arranged within said skirt-like member,-an abrading head having a depending tang,

said tang having a bore to receive said pin,-said skirt-like member being slotted longitudinally,

' and longitudinal projections disposed on said tang and adapted to be received in the slots in the skirt-like member.

4. In a device of the character described, a mandrel having a skirt-like member slotted to form a plurality of prongs, a head having a resilient tang adapted to be received within the skirtlike member, said tang having a plurality of tabs adapted to extend into the slots between the prongs of the skirt-like member, and said tang having slots between the tabsto receive the prongs of the skirt-like member.

5. A device'of the class described'comprising a polishing head constructed and arrangedto be secured to a rotary mandrel which is provided with a plurality of spaced prongs and an inner axially extending pin, said head having an internal tang provided with an axially extending bore to receive said pin and with a plurality of circumferentially spaced axially extending slots outwardly of said bore'for the projection therein of the prongs of the mandrel, when the head is attached thereto, said slots being open at their ends remote from the head, and a'plurality of spaced portions formed on said tang extending open at their ends remote from said side of the head, and a plurality of circumferentially spaced tabs formed on said projecting portion between said slots, said tabs extending longitudinally of said projecting portion said slots and being laterally compressible and resilient.

HERBERT R. BERGER.

having a skirt-like member slotted to beyond said open ends of 

